The Digestive Disease Center at Stanford University has two areas of focus. The first deals with studying host-pathogen interactions in the Gl tract and liver, with an emphasis on host and microbial determinants of pathogenesis and immunity. Infections under study include hepatitis A-D, polio virus, H. pylori, diarrheal agents such as rotavirus, salmonella, E. coli, cholera, Entamoeba histolytica and the Whipple's bacillus. The second focus addresses the cell and molecular biology of digestive epithelia and gastrointestinal immunology with emphasis on normal and abnormal cell growth including malignant transformation, differentiation, development, cell polarity, the cytoskeleton and the role of immune mechanisms in autoimmune Gl diseases, transplantation and Gl infections, both acute and chronic. This focus targets several important digestive diseases including esophageal, pancreatic and colorectal cancer;acute and chronic liver diseases including viral and autoimmune liver disease;pancreatitis, Barrett's esophagus, inflammatory bowel disease and transplant rejection. The center consists of 32 established investigators who blend several clinical and basic science departments. The center consists of five cores. The Administrative Core offers the Pilot/Feasibility Program which provides one year of funding ($25,000/year) to junior investigators or those with a novel or collaborative project;the Named Investigator Program which provides 1 or 2 year 15-25% effort/year support to a promising junior faculty;the Enrichment Program consisting of regular seminars, visiting lectures, and an annual symposium;and a Clinical Component consisting of biostatistical and data management support for clinical studies. The Fluorescence Activated Cell Sorting/lmmunoprobe Core offers an array of services that allow studying single cells and the generation of monoclonal antibodies. The Cell Imaging Core offers stateof- the-art imaging tools including confocal and electron microscopy. The Proteomics and Genomics Core offers the ability to identify disease-associated regulatory changes in genes or their proteins via microarray and mass spectrometry analysis. Finally, the Animal Imaging and Physiology Core offers unparalleled access to state-of-the-art imaging capabilities in a variety of formats and assistance in small animal surgery, organ perfusion and cell isolation. Thus, this center brings together an accomplished group of investigators, creates a highly interactive environment, and makes available state of the art technologies to address important digestive diseases.